By ENID NEMY; David Carr contributed reporting.

Published: August 27, 2009

Dominick Dunne, who gave up producing movies in midlife and reinvented himself as a best-selling author, magazine writer, television personality and reporter whose celebrity often outshone that of his subjects, died Wednesday at his home in Manhattan. He was 83.

The cause was bladder cancer, a family spokesman said. The spokesman had initially declined to confirm the death, saying the family had hoped to wait a day before making an announcement so that Mr. Dunne's obituary would not be obscured by the coverage of Senator Edward M. Kennedy's death.

In the past year Mr. Dunne traveled to the Dominican Republic and Germany for experimental stem-cell treatments to fight his cancer, at one point writing that he and the actress Farrah Fawcett, who died in June, were in the same Bavarian clinic.

He sprang to national prominence with his best-selling novels ''The Two Mrs. Grenvilles'' in 1985 and ''An Inconvenient Woman'' in 1990, both focused on murders in the upper realms of society. He later chronicled high-profile criminal trials and high society as a correspondent and columnist for Vanity Fair magazine.

He achieved perhaps his widest fame from his reporting of the O. J. Simpson murder trial in 1994 and 1995 and later as the host of the program ''Dominick Dunne's Power, Privilege and Justice,'' on what was then Court TV (now TruTV).

Last year, as a postscript to his Simpson coverage, Mr. Dunne defied his doctor's orders and flew to Las Vegas to attend Mr. Simpson's kidnapping and robbery trial.

Mr. Dunne's magazine career was weighted toward the coverage of sensational murder trials. He made no secret of the fact that his sympathy generally lay with the victim, and he was vocal about what he considered the misapplication of justice.

Sympathetic Stance

He never hesitated to admit that his sympathetic stance stemmed from the murder of his daughter, Dominique, by John Sweeney, her ex-boyfriend, in 1982. Ms. Dunne, a 22-year-old actress, was found strangled, and Mr. Sweeney, who was found guilty only of voluntary manslaughter and a misdemeanor for an earlier assault, served less than three years.

''I'm sick of being asked to weep for killers,'' Mr. Dunne often said. ''We've lost our sense of outrage.''

During the trial, Tina Brown, who was the editor of Vanity Fair at the time, suggested he keep a journal. The account, ''Justice: A Father's Account of the Trial of His Daughter's Killer,'' was published in Vanity Fair in 1984.

''He never pretended to be objective in covering trials,'' Graydon Carter, the current editor of Vanity Fair, said Wednesday. ''He was always writing from the point of view of the victim because of what happened to his daughter, and he had a riveting way of knowing, almost like Balzac, what to tell the reader when.''

Mr. Dunne went on to cover the trials of Claus von Bulow, Michael C. Skakel, William Kennedy Smith, Erik and Lyle Menendez, and Phil Spector, as well as the impeachment of President Bill Clinton.

''I realized the power writing has, and it has also helped me deal with my rage,'' he said in an interview with The New York Times for this obituary in 2000. ''It gave me a lifelong commitment not to be afraid to speak out about injustice.''

Mr. Dunne's brother was the writer John Gregory Dunne, the husband of the writer Joan Didion. He died in 2003.

High-Profile Clashes

Mr. Dunne's speaking out led to a lawsuit for slander filed by Gary Condit, a Democratic congressman from California, over remarks Mr. Dunne had made on national radio and television in 2001. Mr. Condit had been scheduled to testify in a deposition about his relationship with Chandra Levy, a federal government intern who disappeared in May 2001 and whose body was found in a Washington park in 2002.

Mr. Dunne quoted a man who asserted that he had heard that Mr. Condit had talked about his relationship with a woman whom he had described as a clinger. Mr. Dunne said this had created an environment that led to Ms. Levy's disappearance. Mr. Condit's suit, originally seeking $11 million in damages, was settled for an undisclosed sum and an apology. A later suit by Mr. Condit was dismissed.

Mr. Dunne also clashed with the Kennedy family about his involvement in the 2002 trial of Mr. Skakel, a first cousin of Robert F. Kennedy Jr. Mr. Skakel was sentenced to 20 years to life in the murder of Martha Moxley in 1975. Her body was found beneath a tree on her parents' property in Greenwich, Conn.

In 2003, in a 14,000-word article in The Atlantic Monthly arguing that the case against his cousin was flawed and had left reasonable doubt, Mr. Kennedy accused Mr. Dunne of intimidating prosecutors and helping to drive the news media into ''a frenzy to lynch the fat kid.''

Mr. Dunne said in The Times interview that he had also been a source of information for a book that Mark Fuhrman was writing about the Skakel trial. He had met him when Mr. Fuhrman testified during the O. J. Simpson murder trial. ''I had some hot information about Skakel,'' Mr. Dunne said, ''and I knew Fuhrman would bring it to attention.''